A veterinarian asked me one time if I handled inner-pack aggression. I winced, took a deep breath and said something non-committal. I’ve given a lot of thought to that over the years. Dogs usually don’t fight in a vacuum. The humans are part of the mix....

New dogs need time to adjust. The rule of thumb is four to twelve months. It does not matter if the dog’s background was bad or pretty good, nor does it matter that your home is wonderful. Change is stressful for most dogs. It will take four months for them to begin...